Camera having photographing elements for photoelectrically converting optical image into image signals

Abstract

A camera is provided with a lens for focusing an optical image of a subject onto an image focusing surface; photographing elements, provided on the image focusing surface, for photoelectrically converting the optical image into image signals, the photographing elements arranged with an arrangement pitch not larger than 7.0 μm; and a diaphragm having a photographing aperture through which the optical image enters into the photographing elements, the diaphragm adjusting the area of the photographing aperture so as to control a light amount of the optical image, wherein when the diaphragm adjusts the photographing aperture so as to have the smallest area, F-number is smaller than 5.6.

What is claimed is:  
     
       1. A camera, comprising: 
       a photographing lens for focusing an optical image onto an image forming surface;  
       a light amount controlling device comprising a first light amount controlling member for adjusting an area of a photographing aperture so as to control a light amount of the optical image and a second light amount controlling member for controlling a light amount of the optical image regardless of the area of the photographing aperture;  
       photographing elements, provided on the image forming surface, for photoelectrically converting the optical image of a subject into image signals, the photographing elements arranged with an arrangement pitch not larger than 7.0 μm; and  
       a signal processing device for processing the image signals;  
       wherein the light amount controlling device starts using the second light amount controlling member when the light amount is further reduced after F-number becomes 5.6 or more by using the first light amount controlling member.  
     
     
       2. The camera of  claim 1 , wherein the light amount controlling device includes a diaphragm on which the photographing aperture is provided. 
     
     
       3. The camera of  claim 1 , wherein the second light amount controlling member is a ND (Neutral Density) filter. 
     
     
       4. The camera of  claim 1 , wherein the second light amount controlling member is a transmittivity controlling member capable of changing the density thereof. 
     
     
       5. The camera of  claim 1 , wherein the second light amount controlling member is a shutter speed controlling member for the photographing elements. 
     
     
       6. The camera of  claim 1 , wherein the signal processing device corrects an influence caused by diffraction of the optical image having passed through the photographing aperture. 
     
     
       7. The camera of  claim 1 , wherein the signal processing device conducts a process to emphasize high frequency components of the image signals. 
     
     
       8. The camera of  claim 7 , wherein the signal processing device changes the extent to emphasize the high frequency component of the image signals in accordance with the F-number. 
     
     
       9. The camera of  claim 1 , wherein the F-number is kept to be not more than 5.6. 
     
     
       10. The camera of  claim 1 , wherein the arrangement pitch is not larger than 5.0 μm.